How to remove rust and tea staining from boat stainless steel
By Marcello Valentini, owner of My Vessel · Updated
The short answer
If the stainless is only stained on the surface, a good metal polish and two microfibre cloths will bring it back: one cloth to rub the polish in and lift the rust, the other to buff it off. If the metal is pitted, it needs a machine polish with professional equipment.
The fingernail test, Autosol and two microfibre cloths: how we get rust off the stainless on the boats we look after around Sydney, and when pitted metal needs a machine polish.
Why boat stainless goes brown
Stainless steel isn't stain-proof. On a boat it lives in salt spray, and the salt that dries on the rails, cleats and fittings starts the little brown spots and the brown haze people call tea staining.
It happens fast. After just one day out on the water, if the boat doesn't get a fresh-water rinse and a soapy wash, you'll see rust on the fittings the next day. And it doesn't pick favourites: rails, cleats, stanchions, the anchor, the bimini frame — every piece of stainless stains the same if it's left too long.
How to remove surface rust and tea staining
This is how we do it on the boats we look after.
- Check the metal first. Run your fingernail over the stain. If it feels smooth, it's surface staining and you can polish it off by hand. If you can feel little holes or rough craters, the metal is pitted — skip to the next section.
- Use a proper metal polish. We use Autosol metal polish (Edel Chrom Glanz). Any quality metal polish made for stainless will work the same way.
- Two microfibre cloths. With the first cloth, apply a small amount of polish and scrub the stained area until the brown lifts. With the second, clean cloth, wipe off the excess and buff it to a shine. It's the same as applying wax: on with one cloth, off with the other.
- Rinse and dry the area when you've finished, so no polish residue is left on the deck.
When the stainless is pitted
Pitting is rust that has eaten small holes into the surface. A hand polish will make it look better for a while, but the rust sits inside the pits and comes straight back.
Pitted stainless needs a machine polish with trade equipment that isn't really available for DIY. That's a job for us: we bring the machine to your berth or mooring.
How to stop the rust coming back
There's no single product that stops it for good. The secret is simply not to let it sit:
- After every day out: rinse the boat with fresh water.
- At least once a month: give the boat a proper wash with boat soap, and scrub the stainless with the brush and soap as you go. Do that, and your stainless will stay mostly rust-free.
- A couple of times a year: a metal polish, as above, to lift what the washes miss and bring back the shine.
The boat lives in salt water. Stay on top of the little things and the stainless stays bright.
Questions people ask
- Can you get rust off stainless steel on a boat?
- Yes. Surface rust and tea staining come off with a metal polish and two microfibre cloths. Pitted stainless needs a machine polish.
- Why does my boat's stainless steel rust?
- Salt spray dries on the metal and starts surface corrosion. Without a fresh-water rinse and a soapy wash, it can show up the day after a trip.
- How do I stop tea staining on my boat?
- Rinse after every outing, wash with boat soap and a brush at least once a month, and polish the stainless a couple of times a year.
- What polish do you use?
- We use Autosol metal polish; any quality metal polish made for stainless works the same way.
Rather we look after it?
Every External Boat Wash includes the stainless, cleaned and dried by hand, and on a regular clean we keep on top of it for you, so the rust never gets a hold. For heavy staining or pitted stainless, tell us when you book and we'll quote the machine polish. See the exact price for your boat in seconds, at your berth or mooring anywhere from Sydney Harbour to Pittwater.
Phone: 0489 275 514